A lot of people disagree with you, because they believe financially supporting Proposition 8 is prima facia evidence of homophobia, just as donating money to the KKK is evidence of racism.
But you're performing logical backflips, and parroting implausible straw man arguments usually proffered by dyed in the wool homophobes to justify their hatred, without actually having any knowledge of Brendan's beliefs, in an attempt to counter arguments and testimonial from people who DO know him and HAVE been negatively affected by his beliefs.
That's why it's my belief that you're being an apologist for bigots. Your "maybe he's against all marriages" argument has been shot down -- don't try it again.